diff options
Diffstat (limited to 'security/selinux/hooks.c')
| -rw-r--r-- | security/selinux/hooks.c | 116 |
1 files changed, 74 insertions, 42 deletions
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 6625699f497..83d06db34d0 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -82,7 +82,6 @@ #include <linux/syslog.h> #include <linux/user_namespace.h> #include <linux/export.h> -#include <linux/security.h> #include <linux/msg.h> #include <linux/shm.h> @@ -107,7 +106,7 @@ int selinux_enforcing; static int __init enforcing_setup(char *str) { unsigned long enforcing; - if (!strict_strtoul(str, 0, &enforcing)) + if (!kstrtoul(str, 0, &enforcing)) selinux_enforcing = enforcing ? 1 : 0; return 1; } @@ -120,7 +119,7 @@ int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE; static int __init selinux_enabled_setup(char *str) { unsigned long enabled; - if (!strict_strtoul(str, 0, &enabled)) + if (!kstrtoul(str, 0, &enabled)) selinux_enabled = enabled ? 1 : 0; return 1; } @@ -234,6 +233,14 @@ static int inode_alloc_security(struct inode *inode) return 0; } +static void inode_free_rcu(struct rcu_head *head) +{ + struct inode_security_struct *isec; + + isec = container_of(head, struct inode_security_struct, rcu); + kmem_cache_free(sel_inode_cache, isec); +} + static void inode_free_security(struct inode *inode) { struct inode_security_struct *isec = inode->i_security; @@ -244,8 +251,16 @@ static void inode_free_security(struct inode *inode) list_del_init(&isec->list); spin_unlock(&sbsec->isec_lock); - inode->i_security = NULL; - kmem_cache_free(sel_inode_cache, isec); + /* + * The inode may still be referenced in a path walk and + * a call to selinux_inode_permission() can be made + * after inode_free_security() is called. Ideally, the VFS + * wouldn't do this, but fixing that is a much harder + * job. For now, simply free the i_security via RCU, and + * leave the current inode->i_security pointer intact. + * The inode will be freed after the RCU grace period too. + */ + call_rcu(&isec->rcu, inode_free_rcu); } static int file_alloc_security(struct file *file) @@ -653,7 +668,7 @@ static int selinux_set_mnt_opts(struct super_block *sb, if (flags[i] == SBLABEL_MNT) continue; rc = security_context_to_sid(mount_options[i], - strlen(mount_options[i]), &sid); + strlen(mount_options[i]), &sid, GFP_KERNEL); if (rc) { printk(KERN_WARNING "SELinux: security_context_to_sid" "(%s) failed for (dev %s, type %s) errno=%d\n", @@ -1403,15 +1418,33 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent isec->sid = sbsec->sid; if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) { - if (opt_dentry) { - isec->sclass = inode_mode_to_security_class(inode->i_mode); - rc = selinux_proc_get_sid(opt_dentry, - isec->sclass, - &sid); - if (rc) - goto out_unlock; - isec->sid = sid; - } + /* We must have a dentry to determine the label on + * procfs inodes */ + if (opt_dentry) + /* Called from d_instantiate or + * d_splice_alias. */ + dentry = dget(opt_dentry); + else + /* Called from selinux_complete_init, try to + * find a dentry. */ + dentry = d_find_alias(inode); + /* + * This can be hit on boot when a file is accessed + * before the policy is loaded. When we load policy we + * may find inodes that have no dentry on the + * sbsec->isec_head list. No reason to complain as + * these will get fixed up the next time we go through + * inode_doinit() with a dentry, before these inodes + * could be used again by userspace. + */ + if (!dentry) + goto out_unlock; + isec->sclass = inode_mode_to_security_class(inode->i_mode); + rc = selinux_proc_get_sid(dentry, isec->sclass, &sid); + dput(dentry); + if (rc) + goto out_unlock; + isec->sid = sid; } break; } @@ -2090,11 +2123,13 @@ static int selinux_bprm_set_creds(struct linux_binprm *bprm) new_tsec->exec_sid = 0; /* - * Minimize confusion: if no_new_privs and a transition is - * explicitly requested, then fail the exec. + * Minimize confusion: if no_new_privs or nosuid and a + * transition is explicitly requested, then fail the exec. */ if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS) return -EPERM; + if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) + return -EACCES; } else { /* Check for a default transition on this program. */ rc = security_transition_sid(old_tsec->sid, isec->sid, @@ -2474,7 +2509,8 @@ static int selinux_sb_remount(struct super_block *sb, void *data) if (flags[i] == SBLABEL_MNT) continue; len = strlen(mount_options[i]); - rc = security_context_to_sid(mount_options[i], len, &sid); + rc = security_context_to_sid(mount_options[i], len, &sid, + GFP_KERNEL); if (rc) { printk(KERN_WARNING "SELinux: security_context_to_sid" "(%s) failed for (dev %s, type %s) errno=%d\n", @@ -2736,6 +2772,7 @@ static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *na static noinline int audit_inode_permission(struct inode *inode, u32 perms, u32 audited, u32 denied, + int result, unsigned flags) { struct common_audit_data ad; @@ -2746,7 +2783,7 @@ static noinline int audit_inode_permission(struct inode *inode, ad.u.inode = inode; rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms, - audited, denied, &ad, flags); + audited, denied, result, &ad, flags); if (rc) return rc; return 0; @@ -2788,7 +2825,7 @@ static int selinux_inode_permission(struct inode *inode, int mask) if (likely(!audited)) return rc; - rc2 = audit_inode_permission(inode, perms, audited, denied, flags); + rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags); if (rc2) return rc2; return rc; @@ -2878,7 +2915,7 @@ static int selinux_inode_setxattr(struct dentry *dentry, const char *name, if (rc) return rc; - rc = security_context_to_sid(value, size, &newsid); + rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL); if (rc == -EINVAL) { if (!capable(CAP_MAC_ADMIN)) { struct audit_buffer *ab; @@ -3035,7 +3072,7 @@ static int selinux_inode_setsecurity(struct inode *inode, const char *name, if (!value || !size) return -EACCES; - rc = security_context_to_sid((void *)value, size, &newsid); + rc = security_context_to_sid((void *)value, size, &newsid, GFP_KERNEL); if (rc) return rc; @@ -3189,24 +3226,20 @@ error: static int selinux_mmap_addr(unsigned long addr) { - int rc = 0; - u32 sid = current_sid(); + int rc; + + /* do DAC check on address space usage */ + rc = cap_mmap_addr(addr); + if (rc) + return rc; - /* - * notice that we are intentionally putting the SELinux check before - * the secondary cap_file_mmap check. This is such a likely attempt - * at bad behaviour/exploit that we always want to get the AVC, even - * if DAC would have also denied the operation. - */ if (addr < CONFIG_LSM_MMAP_MIN_ADDR) { + u32 sid = current_sid(); rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT, MEMPROTECT__MMAP_ZERO, NULL); - if (rc) - return rc; } - /* do DAC check on address space usage */ - return cap_mmap_addr(addr); + return rc; } static int selinux_mmap_file(struct file *file, unsigned long reqprot, @@ -3287,6 +3320,9 @@ static int selinux_file_fcntl(struct file *file, unsigned int cmd, case F_GETLK: case F_SETLK: case F_SETLKW: + case F_OFD_GETLK: + case F_OFD_SETLK: + case F_OFD_SETLKW: #if BITS_PER_LONG == 32 case F_GETLK64: case F_SETLK64: @@ -4474,14 +4510,10 @@ static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, { struct sk_security_struct *sksec = sk->sk_security; int err; - u16 family = sk->sk_family; + u16 family = req->rsk_ops->family; u32 connsid; u32 peersid; - /* handle mapped IPv4 packets arriving via IPv6 sockets */ - if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) - family = PF_INET; - err = selinux_skb_peerlbl_sid(skb, family, &peersid); if (err) return err; @@ -5518,7 +5550,7 @@ static int selinux_setprocattr(struct task_struct *p, str[size-1] = 0; size--; } - error = security_context_to_sid(value, size, &sid); + error = security_context_to_sid(value, size, &sid, GFP_KERNEL); if (error == -EINVAL && !strcmp(name, "fscreate")) { if (!capable(CAP_MAC_ADMIN)) { struct audit_buffer *ab; @@ -5627,7 +5659,7 @@ static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) { - return security_context_to_sid(secdata, seclen, secid); + return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL); } static void selinux_release_secctx(char *secdata, u32 seclen) @@ -5693,7 +5725,7 @@ static void selinux_key_free(struct key *k) static int selinux_key_permission(key_ref_t key_ref, const struct cred *cred, - key_perm_t perm) + unsigned perm) { struct key *key; struct key_security_struct *ksec; |
